TWI429726B - An adhesive agent for engaging the front panel of the display device, an adhesive group for engaging the front panel of the display device, a manufacturing method of the display device, and a display device - Google Patents

Description

An adhesive for bonding a front plate for a display device, an adhesive group for bonding a front plate for a display device, a manufacturing method of the display device, and a display device

The present invention relates to a transparency and a moisture-resistant property of a cured product, and when the polarities of the substrate of the front plate and the front plate are greatly different, the front plate and the substrate can be sufficiently used. Adhesive for the front plate of the display device is attached. Moreover, the present invention relates to a display device using the adhesive for bonding a front plate for a display device, and a method of manufacturing the display device.

In recent years, display devices in which a touch panel or a 3D display function is provided in a flat panel display such as a liquid crystal display, a plasma display, or an organic EL (Electro-Luminescence) display are widely used. This display device is manufactured by bonding a front panel such as a protective panel, an antireflection panel, a touch panel, a lens sheet for 3D display, or a liquid crystal panel for a barrier to a substrate.

In the past, the front plate of the protective film or the like used in the display device is attached to the substrate by the adhesive tape. However, when the adhesive tape is used, it is easy to enter the bubble or the foreign matter when the front plate is bonded, or Positioning becomes difficult when fitting. Patent Documents 1 and 2 disclose coating-type adhesives in place of the adhesive tape. However, the adhesive disclosed in Patent Document 1 is composed of a hydrophobic material mainly composed of synthetic rubber, and thus has a problem of poor affinity with a hydrophilic substrate such as glass. Further, the adhesive disclosed in Patent Document 2 has a problem that the front plate and the substrate cannot be sufficiently adhered.

As an adhesive having good affinity with a hydrophilic substrate, for example, Patent Document 3 discloses a resin composition comprising an alkyl acrylate and an acrylate having a hydroxyl group. However, since the resin composition disclosed in Patent Document 3 is a mixture of resins having different polarities, there is a problem in compatibility, and when a light is irradiated, especially when exposed to a high-humidity environment, a hardened material is likely to occur. The problem of white turbidity.

Further, the conventional adhesive has a problem in that the polarity of the base material of the front plate and the front plate to be bonded is greatly different, and the front plate is peeled off.

Patent Document 1: Japanese Patent Laid-Open Publication No. 2005-015598

Patent Document 2: Japanese Patent Laid-Open No. 7-134212

Patent Document 3: Japanese Laid-Open Patent Publication No. Hei 9-258023

An object of the present invention is to provide a transparency and a moisture-resistant property of a cured product which are excellent in moisture resistance and which can sufficiently adhere to a front plate and a substrate when the polarity of the substrate of the front plate and the front plate to be bonded is greatly different. An adhesive for bonding the front plate for a display device. Further, an object of the present invention is to provide a display device using the adhesive for bonding a front plate for a display device.

The adhesive for bonding the front plate for a display device of the present invention is an adhesive for bonding the substrate of the display device to the front plate, and contains a monofunctional radical having a hydrophilic group and a hydrophobic group in the molecule. A polymerizable compound, a homopolymer of the monofunctional radically polymerizable compound, a polyfunctional radically polymerizable compound, and a photoradical polymerization initiator.

The invention is described in detail below.

The present inventors have found that a monofunctional radical polymerizable compound having a hydrophilic group and a hydrophobic group in the molecule, a homopolymer of the monofunctional radical polymerizable compound, and a polyfunctional radical polymerizable compound When used in combination, transparency and excellent moisture resistance of the cured product can be obtained, and when the polarities of the substrate of the front plate and the front plate are greatly different, the front plate and the substrate can be sufficiently used. The present invention is completed by laminating an adhesive for a front plate for a display device.

The adhesive for bonding the front sheet for a display device of the present invention contains a monofunctional radical polymerizable compound having a hydrophilic group and a hydrophobic group in the molecule (hereinafter also referred to simply as a monofunctional radical polymerizable compound). By using a monofunctional one as a radically polymerizable compound, a homopolymer having high compatibility with the radically polymerizable compound can be obtained without gelation. In addition, when the monofunctional radically polymerizable compound has a hydrophilic group and a hydrophobic group in the molecule, even if the front plate and the substrate are made of a material having a very different polarity, it can be sufficiently continued These are the same. Further, since it has a hydrophilic group, it is possible to suppress white turbidity of the cured product even when exposed to a high-humidity environment.

Examples of the hydrophilic group include a (poly)ethylene glycol group, a (poly)propylene glycol group, a (poly)butylene glycol group, and a (poly)2-hydroxypropanediol group. Among them, the hydrophilicity is strong, and the obtained adhesive is preferably a (poly)ethylene glycol group from the viewpoint of excellent adhesion to a substrate having a high polarity.

Examples of the hydrophobic group include a phenyl group, an alkyl group, an alkylphenyl group, an isobornyl group, and a tricyclodecane dimethanol group. Among them, a phenyl group is preferred in terms of good affinity with the resin.

Specific examples of the monofunctional radically polymerizable compound having a hydrophilic group and a hydrophobic group in the molecule include phenoxy diethylene glycol acrylate and 2-ethylhexyl diethylene glycol acrylate. , nonylphenoxy diethylene glycol acrylate, and the like. Among them, the compound represented by the following formula (1) is preferable in that the adhesive agent for bonding the front sheet for a display device is excellent in adhesion to a substrate.

In the formula (1), R ¹ represents hydrogen or a methyl group, R ² represents a linear or branched saturated aliphatic hydrocarbon group having 1 to 6 carbon atoms, or a 2-hydroxypropyl group, and R ³ represents the following formula: The substituent represented by (2-1), (2-2), (2-3), or (2-4), and n represents an integer of 1 to 6.

In the formula (2-1), R ⁴ represents hydrogen or a linear or branched alkyl group having 1 to 12 carbon atoms.

In the formula (1), R ^{2 may} be a linear or branched saturated aliphatic hydrocarbon group having 1 to 6 carbon atoms, and preferably a methylene group, an ethyl group or a pendant propyl group.

Examples of the monofunctional radically polymerizable compound having a substituent represented by the formula (2-1) include phenoxyethyl acrylate ("Light Acrylate PO-A" manufactured by Kyoeisha Chemical Co., Ltd., Daicel- "EBECRYL 110" manufactured by Cytec, phenyl diethylene glycol acrylate ("Light Acrylate P-200A" manufactured by Kyoeisha Chemical Co., Ltd.), and EO (ethylene oxide) addition of nonylphenol Acrylate ("Light Acrylate NP-4EA" manufactured by Kyoeisha Chemical Co., Ltd.), acrylic acid 2-Hydroxy-3-phenoxypropyl ester ("EPOXY ESTER M-600A" manufactured by Kyoeisha Chemical Co., Ltd.) and the like.

Examples of the monofunctional radically polymerizable compound having a substituent represented by the formula (2-2) include dicyclopentenyloxyethyl acrylate ("Fancryl FA-512AS" manufactured by Hitachi Chemical Co., Ltd.).

The acid value of the monofunctional radically polymerizable compound is not particularly limited, and a preferred upper limit is 0.5 mgKOH/g. When the acid value of the monofunctional radically polymerizable compound exceeds 0.5 mgKOH/g, the electrode or the like of the obtained display device may be corroded. The upper limit of the acid value of the above monofunctional radically polymerizable compound is preferably 0.1 mgKOH/g.

The content of the monofunctional radically polymerizable compound is not particularly limited, and is a total of the monofunctional radically polymerizable compound, the homopolymer of the monofunctional radically polymerizable compound, and the polyfunctional radically polymerizable compound. 100 parts by weight, preferably a lower limit of 5 parts by weight, preferably an upper limit of 90 parts by weight. When the content of the monofunctional radically polymerizable compound is less than 5 parts by weight, the viscosity of the adhesive for obtaining the front sheet for a display device may be too high, and coating may be difficult. When the content of the monofunctional radical polymerizable compound exceeds 90 parts by weight, the obtained adhesive for bonding the front plate for a display device may be deformed when the front plate and the substrate are bonded together, or may be deformed, or The viscosity becomes too low. A more preferred lower limit of the content of the above monofunctional radically polymerizable compound is 10 parts by weight, and a more preferred upper limit is 80 parts by weight.

The adhesive for bonding the front plate for a display device of the present invention contains a homopolymer of the above monofunctional radically polymerizable compound. By using the above single officer The homopolymer of the radically polymerizable compound can be used as a polymer which is prepared by reducing the hardening shrinkage, improving the adhesion or dimensional stability, or adjusting the viscosity, and can suppress the white turbidity of the cured product after the light irradiation.

A preferred upper limit of the glass transition temperature of the homopolymer of the above monofunctional radically polymerizable compound is 25 °C. When the glass transition temperature of the homopolymer of the monofunctional radically polymerizable compound exceeds 25 ° C, the obtained display device may have poor impact resistance.

The lower limit of the weight average molecular weight of the homopolymer of the above monofunctional radically polymerizable compound measured by gel permeation chromatography (GPC, Gel Permeation Chromatography) is 3,000, preferably the upper limit is 200,000. . When the weight average molecular weight of the homopolymer of the monofunctional radically polymerizable compound is less than 3,000, the obtained adhesive for bonding the front plate for a display device becomes poor in adhesion to the front plate or the substrate. , or in the case of insufficient viscosity. When the weight average molecular weight of the homopolymer of the monofunctional radically polymerizable compound exceeds 200,000, the viscosity of the obtained adhesive for bonding the front plate for a display device becomes too high, and coating becomes difficult. The situation. The lower limit of the weight average molecular weight of the homopolymer of the monofunctional radically polymerizable compound is preferably 20,000, and more preferably the upper limit is 80,000.

In addition, as a column for measuring the weight average molecular weight in terms of polystyrene by GPC, for example, LF-804 (manufactured by SHOKO Co., Ltd.) or the like can be mentioned.

The content of the homopolymer of the monofunctional radically polymerizable compound is not particularly limited, and the monofunctional radically polymerizable compound, the homopolymer of the monofunctional radically polymerizable compound, and the above polyfunctional free The total amount of the base polymerizable compound is 100 parts by weight, preferably 10 parts by weight, and preferably 80 parts by weight. When the content of the homopolymer of the monofunctional radically polymerizable compound is less than 10 parts by weight, the curing shrinkage is increased, and the obtained adhesive for bonding the front sheet for a display device is bonded to the front sheet or the laminate. If the substrate of the front plate is inferior in adhesion, deformation may occur or the viscosity may be insufficient. When the content of the homopolymer of the monofunctional radically polymerizable compound exceeds 80 parts by weight, the viscosity of the obtained adhesive for bonding the front plate for a display device becomes too high, and coating becomes difficult. Happening. A more preferred lower limit of the content of the homopolymer of the monofunctional radically polymerizable compound is 20 parts by weight, and a more preferred upper limit is 70 parts by weight.

The adhesive for bonding the front sheet for a display device of the present invention contains a polyfunctional radical polymerizable compound. By containing the above polyfunctional radically polymerizable compound, the adhesive for bonding the front plate for a display device of the present invention can be made into a crosslinked body after curing, and the shape can be maintained at a high temperature.

Examples of the polyfunctional radically polymerizable compound include polyfunctional epoxy acrylates such as bisphenol A diglycidyl ether diacrylate and polyethylene glycol diepoxypropyl ether diacrylate, or three. Hydroxymethylpropane triacrylate, tetramethylol methane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butanediol diacrylate Ester, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, tricyclodecane dimethanol diacrylate, and the like. These polyfunctional radically polymerizable compounds may be used singly or in combination of two or more.

Among them, in terms of having a hydrophilic group and a hydrophobic group in the molecule In other words, tricyclodecane dimethanol diacrylate is preferred.

The content of the polyfunctional radically polymerizable compound is not particularly limited, and is a total of the monofunctional radically polymerizable compound, the homopolymer of the monofunctional radically polymerizable compound, and the polyfunctional radically polymerizable compound. The lower limit is 100 parts by weight, preferably 1 part by weight, and preferably the upper limit is 30 parts by weight. When the content of the polyfunctional radically polymerizable compound is less than 1 part by weight, crosslinking may be insufficient, and variation may occur at a high temperature. When the content of the polyfunctional radically polymerizable compound exceeds 30 parts by weight, the content may become too high and the impact resistance may be lowered. A more preferred lower limit of the content of the above polyfunctional radically polymerizable compound is 5 parts by weight, and a more preferred upper limit is 20 parts by weight.

The adhesive for bonding the front sheet for a display device of the present invention contains a photoradical polymerization initiator.

The photoradical polymerization initiator is not particularly limited, and examples thereof include a benzophenone-based compound, an acetophenone-based compound, a fluorenylphosphine oxide-based compound, a titanocene-based compound, and an oxime ester-based compound. Benzoin ether compound, 9-oxosulfur (thioxanthone) and so on.

Among the above-mentioned photoradical polymerization initiators, for example, IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACURE OXE01, and Lucirin TPO (both are BASF Japan) Made by the company), benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether (all of which are manufactured by Tokyo Chemical Industry Co., Ltd.). Among them, in terms of a wide absorption wavelength region, it is preferably IRGACURE 651, IRGACURE 907, benzoin isopropyl ether, and Lucirin TPO. These photoradical polymerization initiators may be used singly or in combination of two or more.

The content of the photoradical polymerization initiator is not particularly limited, and is a total of the monofunctional radical polymerizable compound, the homopolymer of the monofunctional radically polymerizable compound, and the polyfunctional radical polymerizable compound. The lower limit is preferably 0.5 parts by weight, preferably 10 parts by weight, based on 100 parts by weight. When the content of the photoradical polymerization initiator is less than 0.5 part by weight, the polymerization is not sufficiently performed, or the hardening reaction of the obtained adhesive for bonding the front plate for a display device becomes too slow. . When the content of the photoradical polymerization initiator is more than 10 parts by weight, the hardening reaction of the obtained adhesive for bonding the front plate for a display device becomes too fast, and the workability is lowered or obtained. The adhesive for bonding the front plate for the display device becomes a non-uniform cured product. A more preferred lower limit of the content of the above photoradical polymerization initiator is 1 part by weight, and a more preferred upper limit is 5 parts by weight.

The adhesive for bonding the front sheet for a display device of the present invention preferably contains a thermal radical polymerization initiator.

The thermal radical polymerization initiator may be used as long as it is decomposed at a temperature of 100 ° C or lower to generate a radical, and may be selected in consideration of a film formation temperature, a crosslinking temperature, a storage stability, and the like. . Among them, in terms of good low-temperature hardenability, a decomposition temperature of 10 hours in the half-life period of 70 ° C or less can be preferably used.

Examples of the thermal radical polymerization initiator include an azo compound, an organic peroxide, and the like. Among them, an organic peroxide is preferred.

Examples of the above organic peroxide include 2,5-dimethylhexane-2,5-dihydroxy peroxide and 2,5-dimethyl-2,5-di (t-butyl group). Oxidation) hexyne-3, di-tert-butyl peroxide, tributyl cumene peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, Dicumyl peroxide, α,α'-bis(t-butylperoxyisopropyl)benzene, 4,4-bis(t-butylperoxy)-n-butyl valerate, 2,2-double (T-butyl peroxy) butane, 1,1-bis(t-butylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)-3,3,5-trimethyl Cyclohexane, tert-butyl peroxybenzoate, benzamidine peroxide, tert-butyl peroxyacetate, methyl ethyl ketone peroxide, tert-butyl hydroperoxide, hydroperoxide Alkane, hydroxyheptyl peroxide, chlorohexanone peroxide, octyl peroxide, cerium peroxide, laurel peroxide, cumene peroxyoctanoate, cumene peroxy neodecanoate, peroxidation Succinic acid, acetonitrile peroxide, tert-butyl peroxy-2-ethylhexanoate, meta-toluene peroxide, tert-butyl peroxyisobutyrate 2,4-dichlorobenzoyl peroxide, benzoyl peroxide, tertiary-hexyl pivalate ester and the like. These thermal radical polymerization initiators may be used singly or in combination of two or more.

The content of the thermal radical polymerization initiator is not particularly limited, and is a total of the monofunctional radically polymerizable compound, the homopolymer of the monofunctional radically polymerizable compound, and the polyfunctional radical polymerizable compound. The lower limit is preferably 0.1 part by weight, preferably 10 parts by weight, based on 100 parts by weight. When the content of the above-mentioned thermal radical polymerization initiator is less than 0.1 part by weight, the polymerization may not proceed sufficiently, or the hardening reaction of the obtained adhesive for bonding the front plate for a display device may become too slow. . If the content of the above thermal radical polymerization initiator exceeds 10 parts by weight, it is hardened At the time of foaming, the storage stability of the obtained adhesive for bonding the front plate for a display device is deteriorated, and the viscosity is increased. A more preferred lower limit of the content of the above thermal radical polymerization initiator is 1 part by weight.

The adhesive for bonding the front sheet for a display device of the present invention may contain a decane coupling agent as a adhesion promoter in a range not inhibiting the object of the present invention.

Specific examples of the decane coupling agent include vinyl triethoxy decane, vinyl tris(β-methoxyethoxy) decane, and γ-methyl propylene methoxy propyl trimethoxy group. Decane, vinyltriethoxydecane, γ-glycidoxypropyltrimethoxydecane, γ-glycidoxypropyltriethoxydecane, β-(3,4-epoxy ring Hexyl)ethyltrimethoxydecane, γ-chloropropylmethoxydecane, vinyltrichloromethane, γ-mercaptopropyltrimethoxydecane, γ-aminopropyltriethoxydecane, N-β (Aminoethyl)-γ-aminopropyltrimethoxydecane, and the like. These decane coupling agents may be used singly or in combination of two or more.

The content of the above-mentioned decane coupling agent is not particularly limited, and is 100 parts by weight based on the total of the monofunctional radically polymerizable compound, the homopolymer of the monofunctional radically polymerizable compound, and the polyfunctional radical polymerizable compound. A preferred lower limit is 0.01 parts by weight, and a preferred upper limit is 5 parts by weight. When the content of the above decane coupling agent is less than 0.01 part by weight, the effect of improving the adhesion of the obtained adhesive for bonding the front plate for a display device may not be sufficiently obtained. When the content of the above decane coupling agent exceeds 5 parts by weight, the remaining decane coupling agent may bleed out. A more preferred lower limit of the content of the above decane coupling agent is 0.5 part by weight.

The adhesive for bonding the front sheet for a display device of the present invention may contain a filler in a range not inhibiting the object of the present invention.

The filler is not particularly limited, and examples thereof include an inorganic filler and an organic filler.

The inorganic filler is not particularly limited, and examples thereof include talc, cerium oxide, smectite, bentonite, calcium carbonate, magnesium carbonate, alumina, montmorillonite, diatomaceous earth, magnesium oxide, titanium oxide, and magnesium hydroxide. , aluminum hydroxide, glass beads, barium sulfate, gypsum, calcium citrate, sericite activated clay and so on.

The organic filler is not particularly limited, and examples thereof include polyester fine particles, polyurethane fine particles, vinyl polymer fine particles, and acrylic polymer fine particles.

These fillers may be used singly or in combination of two or more.

The method for producing the adhesive for bonding the front plate for a display device of the present invention is not particularly limited, and examples thereof include a uniform disperser, a homomixer, a universal agitator, a planetary mixer, a kneader, a three-roll mill, and the like. In the mixer, the monofunctional radically polymerizable compound, the homopolymer of the monofunctional radically polymerizable compound, the polyfunctional radically polymerizable compound, the photoradical polymerization initiator, and the above thermal radical polymerization A method of mixing an initiator or an additive such as the above decane coupling agent.

The viscosity of the adhesive for bonding the front plate for a display device of the present invention is not particularly limited, and a preferred lower limit of the viscosity measured by an E-type viscometer at 25 ° C and 2.5 rpm is 20 mPa. s, the upper limit is preferably 500,000 mPa. s. If the above viscosity is less than 20 mPa. s, there is a case where the adhesive for bonding the front plate for the display device is discharged during coating. If the above is used for fitting The adhesive of the front plate of the display device has a viscosity of more than 500,000 mPa. s, there is a case where coating becomes difficult. The lower limit of the viscosity of the above adhesive for bonding the front plate for the display device is 50 mPa. s, the upper limit is better 200,000 mPa. s.

The manufacturing method of the display device is to bond the substrate and the front plate with an adhesive for bonding the front plate for the display device, and to apply the adhesive for bonding the front plate for a display device of the present invention to the above a step of bonding at least one of the substrate and the front plate; and bonding the substrate and the front plate to the step of curing the adhesive for bonding the front plate for the display device by irradiation of light, The method is also one of the inventions.

In the step of applying the adhesive for bonding the front plate for a display device of the present invention to at least one of the substrate and the front plate, the front plate of the present invention for bonding the display device The agent may be applied to the front panel or to the substrate to which the front panel is attached. The thickness of the adhesive layer obtained by the adhesive for bonding the front plate for a display device of the present invention after coating can be appropriately determined depending on the material, use, and the like, but is usually about 1 to 200 μm.

Examples of the front plate include a protective panel such as glass, polycarbonate, or acrylic resin; a resistive or capacitive touch panel; a lenticular lens for 3D display; or a parallax barrier. LCD panel for barriers, etc.

Further, examples of the substrate to which the front plate is bonded include a liquid crystal panel module, an organic EL panel module, a plasma display, and electronic paper.

Further, the adhesive for bonding the front plate for a display device of the present invention can also be used for the subsequent bonding of the different front plates.

The coating method of the adhesive for bonding the front plate for a display device of the present invention is not particularly limited, and for example, it can be carried out using a coater such as a roll coater or a die coater. In particular, in order to apply uniformly, it is preferable to apply to the substrate by a die coater or the like while heating.

In the step of bonding the substrate and the front plate to harden the adhesive for bonding the front plate for a display device by irradiating light, the adhesive for bonding the front plate for a display device of the present invention may be used. After coating, it is hardened by irradiating light of a wavelength of 300 nm to 400 nm and a cumulative amount of light of 300 to 3000 mJ/cm ² .

The light source for illuminating the light for curing the adhesive for bonding the front plate for a display device of the present invention is not particularly limited, and examples thereof include a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, and an excimer laser. Injection, chemical lamp, black light, microwave excited mercury lamp, metal halide lamp, sodium lamp, halogen lamp, xenon lamp, fluorescent lamp, sunlight, electron beam irradiation device, etc. These light sources may be used singly or in combination of two or more. When these light sources are selected, they can be suitably selected according to the absorption wavelength of the photoradical polymerization initiator.

Examples of the irradiation order of the adhesive for bonding the front plate for a display device of the present invention as the light source include, for example, simultaneous irradiation of various light sources, sequential irradiation with a time difference, combined irradiation with simultaneous irradiation, and the like. Use any method of irradiation.

In the cured product of the adhesive for bonding the front plate for a display device of the present invention, a preferred lower limit of the transmittance of light having a wavelength of 405 nm when the thickness is 300 μm is 90%. If the above penetration rate is less than 90%, then it is obtained. The display device is in a case where the optical characteristics are poor.

The cured product of the adhesive for bonding the front plate for display elements of the present invention preferably has a haze of 2 or less when the thickness is 300 μm. If the above haze value exceeds 2, the obtained display element may become cloudy. The above haze value is more preferably 1 or less.

As a method of manufacturing a display device using the adhesive for bonding a front plate for a display device of the present invention, for example, an adhesive for bonding a front plate for a display device of the present invention is applied to a front plate or a laminate. The entire surface or a part of the base material of the front plate is bonded to the base plate and the front plate by an adhesive for bonding the front plate for a display device of the present invention, and is produced by irradiating ultraviolet rays.

Fig. 1 is a cross-sectional view showing an example of a display device using the adhesive for bonding a front plate for a display device of the present invention. The display device shown in FIG. 1 is bonded to the substrate 2 and the substrate 2 via an adhesive 3 for bonding the front plate for a display device. Further, the front plate 1 has the light shielding portion 4 and the light transmitting portion 5, and it is difficult for the light incident from the front plate side to reach the portion of the adhesive 3 for bonding the front plate for the display device, which is located below the light shielding portion 4.

In the case where a light-shielding portion such as an opaque electrode or a black matrix is formed on the substrate or the front plate as in the display device shown in FIG. 1, the light-shielding portion can be attached by heating while irradiating the light. The display device is hardened with an adhesive of the front plate.

When the adhesive for bonding the front plate for a display device is cured by irradiation with light and heating, the adhesive for bonding the front plate for a display device of the present invention preferably contains the above-mentioned thermal radicals. Polymerization initiator.

Further, the adhesive for bonding the front plate for a display device of the present invention may be a combination of two or more kinds of adhesives, and the following adhesive group for bonding the front plate for a display device may be used under atmospheric pressure. Or sealing the front plate and the substrate to be sealed under reduced pressure, and the adhesive agent for bonding the front plate for the display device is composed of the adhesive for bonding the front plate for the display device of the present invention. a high peripheral adhesive (dam agent), and a filling agent for filling the inner portion of the present invention for bonding the front plate for a display device with a lower viscosity than the peripheral adhesive. Use an adhesive (filler).

The adhesive group for bonding the front plate for the display device is used for the adhesive group of the substrate of the display device and the front plate, and the lining agent for the substrate and the front plate is attached to the peripheral portion of the display device. And the filler of the base material and the front plate on the inner side of the damper; the damper and the filler are the adhesives for bonding the front plate of the display device of the present invention, and respectively contain the same a monofunctional radically polymerizable compound, a homopolymer of the monofunctional radically polymerizable compound, a polyfunctional radically polymerizable compound, and a photoradical polymerization initiator; the perianning agent is compared with the above filler The homopolymer of the monofunctional radically polymerizable compound has a high content ratio, and the viscosity of the above-mentioned cofferdam is measured using an E-type viscometer at 25 ° C and 2.5 rpm using an E-type viscometer at 25 ° C, 2.5. The viscosity of the above filler measured under the condition of rpm is 30,000 to 10,000 times, and the adhesive group is also one of the inventions.

In the present specification, the "peripheral portion of the display device" means a portion of the display device from the display pixel portion to the end portion of the display device.

By using a cofferant for the substrate and the front plate at the peripheral portion of the display device, and a filler for the substrate and the front plate on the inner side of the cofferdam, the same material is used, and the cofferdam is used. When the viscosity of the filler is set to a specific ratio, an adhesive for adhering to the front plate of the display device which can suppress the leakage of the adhesive when the substrate and the front plate are bonded and the image of the display device can be obtained. In the method of using a binder group composed only of a cofferant and a filler, the cofferdam can be used by applying a cohesive agent having a high viscosity to the outside of the filler having a low viscosity and excellent coatability. The agent prevents leakage of the filler when the substrate and the front plate are bonded, but when the transparent material is used for both the cofferdam and the filler, it is also present at the boundary portion of the cofferant and the filler. The situation in which the image produces strain.

In the adhesive set for bonding a front plate for a display device of the present invention, the damper and the filler are the adhesives for bonding the front plate for a display device of the present invention. In other words, the damper and the filler contain a monofunctional radical polymerizable compound having a hydrophilic group and a hydrophobic group in the molecule, a homopolymer of the monofunctional radical polymerizable compound, and a polyfunctional radical polymerizable compound. And photoradical polymerization initiators.

Further, the damper and the filler contain the same monofunctional radically polymerizable compound and a homopolymer of the monofunctional radically polymerizable compound, and the damper is monofunctional radical compared to the filler. The content ratio of the homopolymer of the polymerizable compound is high.

The content of the monofunctional radically polymerizable compound in the above-mentioned damper is not particularly limited, and is a homopolymer of a monofunctional radically polymerizable compound, a monofunctional radically polymerizable compound, and a polyfunctional radical polymerization property. The total amount of the compound is 100 parts by weight, preferably the lower limit is 3 parts by weight, and the upper limit is preferably 50 parts by weight. When the content of the monofunctional radically polymerizable compound in the damper is less than 3 parts by weight, the viscosity of the obtained damper may be too high, and coating may be difficult. If the content of the monofunctional radically polymerizable compound in the above-mentioned damper exceeds 50 parts by weight, the viscosity of the obtained damper becomes too low, and the damper or filler is applied to the substrate and the front plate. Leakage, or the hardening shrinkage of the cofferdam becomes large and deformed. A more preferred lower limit of the content of the monofunctional radically polymerizable compound in the above-mentioned damper is 5 parts by weight, and a more preferred upper limit is 30 parts by weight.

The content of the monofunctional radically polymerizable compound in the above-mentioned filler is not particularly limited, and is a monofunctional radical polymerizable compound, a homopolymer of a monofunctional radically polymerizable compound, and a polyfunctional radical polymerizable compound. A total of 100 parts by weight, preferably a lower limit of 10 parts by weight, preferably an upper limit of 95 parts by weight. When the content of the monofunctional radically polymerizable compound in the above filler is less than 10 parts by weight, the viscosity of the obtained filler may become too high, and coating may be difficult. When the content of the monofunctional radically polymerizable compound in the filler exceeds 95 parts by weight, the curing shrinkage of the filler may be increased and deformed. A more preferred lower limit of the content of the monofunctional radically polymerizable compound in the above filler is 30 parts by weight, and a more preferred upper limit is 90 parts by weight.

The content of the homopolymer of the monofunctional radically polymerizable compound is higher than that of the above-mentioned filler.

The content of the homopolymer of the monofunctional radically polymerizable compound in the above-mentioned cofferdam is as long as the content of the homopolymer is higher than that of the above filler. It is preferably 30 parts by weight, preferably 30 parts by weight, based on 100 parts by weight of the total of the monofunctional radically polymerizable compound, the homopolymer of the monofunctional radically polymerizable compound, and the polyfunctional radically polymerizable compound. The upper limit is 95 parts by weight. When the content of the homopolymer of the monofunctional radically polymerizable compound in the above-mentioned cofferdam is less than 30 parts by weight, the hardening shrinkage is increased, and the obtained cofferdam becomes the base of the front plate or the front plate. The poor adhesion of the material may be deformed, or the viscosity of the cofferdam may be insufficient to cause the cofferdam or filler to leak out when the substrate and the front plate are bonded. When the content of the homopolymer of the monofunctional radically polymerizable compound in the damper is more than 95 parts by weight, the viscosity of the damper may be too high, and coating may be difficult. A more preferred lower limit of the content of the homopolymer of the monofunctional radically polymerizable compound in the above-mentioned damper is 50 parts by weight, and a more preferred upper limit is 90 parts by weight.

The content of the homopolymer of the monofunctional radically polymerizable compound in the above-mentioned filler is not particularly limited as long as it is lower than the above-mentioned cofferdam, and is not particularly limited with respect to the monofunctional radically polymerizable compound. The total of 100 parts by weight of the homopolymer of the functional radical polymerizable compound and the polyfunctional radically polymerizable compound is preferably 1 part by weight, and preferably 70 parts by weight. When the content of the homopolymer of the monofunctional radically polymerizable compound in the above filler is less than 1 part by weight, the curing shrinkage is increased, and the obtained filler becomes a substrate with the front sheet or the front sheet to be bonded. Then the poorer or deformed situation. When the content of the homopolymer of the monofunctional radically polymerizable compound in the above filler exceeds 70 parts by weight, the viscosity of the obtained filler becomes too high, and coating becomes difficult. Fill in above A more preferred lower limit of the content of the homopolymer of the monofunctional radically polymerizable compound in the charge is 5 parts by weight, and a more preferred upper limit is 50 parts by weight.

The lower limit of the ratio of the viscosity of the above-mentioned compensator measured by an E-type viscometer at 25 ° C and 2.5 rpm to the viscosity of the above-mentioned filler measured at 25 ° C and 2.5 rpm using an E-type viscometer is 3 times, the upper limit is 10,000 times. If the viscosity of the above-mentioned sputum agent is less than three times the viscosity of the above-mentioned filler, there is a case where the damper or the filler leaks when the substrate and the front plate are bonded. When the viscosity of the above-mentioned damper exceeds 10,000 times the viscosity of the above-mentioned filler, coating of the damper may be difficult, or strain of the substrate due to the difference in curing shrinkage may occur. A preferred lower limit of the ratio of the viscosity of the damper to the viscosity of the filler is 5 times, preferably 5,000 times, more preferably 10 times, and even more preferably 1000 times.

Regarding the above-mentioned cofferdam, the preferred lower limit of the viscosity measured by an E-type viscometer at 25 ° C and 2.5 rpm is 3000 mPa. s, the upper limit is preferably 500,000 mPa. s. If the viscosity of the above cognac agent is less than 3000 mPa. s, there is a case where the cofferant or the filler flows out during application or when the substrate and the front plate are bonded. If the viscosity of the above cognac agent exceeds 500,000 mPa. s, the application of the cofferdam becomes difficult. The lower limit of the viscosity of the above cofferdam is 5000 mPa. s, the upper limit is 300,000 mPa. s.

Regarding the above filler, the preferred lower limit of the viscosity measured by an E-type viscometer at 25 ° C and 2.5 rpm is 10 mPa. s, the upper limit is preferably 30,000 mPa. s. If the viscosity of the above filler is less than 10 mPa. s, there is a case where the hardening shrinkage is increased and the strain is generated. If the viscosity of the above filler exceeds 30,000 mPa. s, there is a case where the application of the filler becomes difficult. on The lower limit of the viscosity of the adhesive for bonding the front plate for the display device is 100 mPa. s, the upper limit is better 10,000 mPa. s.

The manufacturing method of the display device is a method of bonding a substrate and a front plate with an adhesive for bonding a front plate for a display device, and having a peripheral agent at at least one of the substrate and the front plate, and applying the cofferdam a step of forming a frame, applying a filler to the frame of the coated ampoules, and bonding the substrate and the front plate via the damper and the filler to illuminate the light And the step of curing the damper and the filler, wherein the damper and the filler are the dampers and fillers of the adhesive group of the present invention for bonding a front plate for a display device, The display device manufacturing method is also one of the inventions.

In the step of coating the cofferdam into a frame at a peripheral portion of at least one of the substrate and the front plate, the cofferant may be applied to the front plate or may be applied to the front plate. On the substrate. The thickness of the adhesive layer obtained from the cofferdam after application can be appropriately determined depending on the material, use, and the like, and is usually about 1 to 200 μm.

In the step of applying the damper to the peripheral portion of at least one of the base material and the front plate, the method of applying the damper is not particularly limited, and for example, a dispensing or a wire may be used. Web printing and other methods.

Further, in the step of applying a filler to the frame of the cofferdam to be applied, the method of applying the filler is not particularly limited, and examples thereof include dispensing, screen printing, inkjet, and the like. The method.

In order to apply uniformly, the damper and the filler are preferably applied while being heated.

a step of bonding the base material and the front plate to the base sheet via the damper and the filler, and curing the damper and the filler by irradiation with light, as the sputum agent and the above The light which is hardened by the filler is preferably a light having a wavelength of 300 nm to 400 nm and a cumulative light amount of 300 to 3000 mJ/cm ² .

The light source for illuminating the light for curing the damper and the filler is not particularly limited, and examples thereof include a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, an excimer laser, a chemical lamp, and a black light. , microwave excited mercury lamp, metal halide lamp, sodium lamp, halogen lamp, xenon lamp, fluorescent lamp, sunlight, electron beam irradiation device, and the like. These light sources may be used singly or in combination of two or more. When these light sources are selected, they can be appropriately selected depending on the absorption wavelength of the photoradical polymerization initiator.

Examples of the irradiation order of the light from the light source include simultaneous irradiation of various light sources, sequential irradiation with a time difference, combined irradiation of simultaneous irradiation and sequential irradiation, and any irradiation method.

In the cured product of the above-mentioned cofferdam and the above filler, a preferred lower limit of the transmittance of light having a wavelength of 405 nm when the thickness is 300 μm is 90%. If the above-described transmittance is less than 90%, the obtained display device may be inferior in optical characteristics.

When the adhesive group for bonding the front plate for a display device of the present invention is used, when the display device shown in FIG. 1 is formed with a light-shielding portion such as an opaque electrode or a black matrix on the substrate or the front plate. The cofferdam or filler located in the light shielding portion can be hardened by heating while irradiating the light.

The above-mentioned cofferdam or the above filling is performed by irradiating light and heating In the case where the agent is cured, the above-mentioned damper and the above filler preferably contain the above-mentioned thermal radical polymerization initiator.

The adhesive agent for bonding the front plate for a display device of the present invention and the adhesive agent for bonding the front plate for a display device of the present invention can be preferably used in a display device. The display device is one which is an adhesive for bonding a front plate for a display device of the present invention or an adhesive agent for bonding a front plate for a display device of the present invention, and is also one of the inventions.

According to the present invention, it is possible to provide a transparency and a moisture-resistant property of the cured product, and when the polarities of the substrate of the front plate and the front plate are greatly different, the front plate and the substrate can be sufficiently adhered. An adhesive for bonding the front plate for a display device. Moreover, according to the present invention, it is possible to provide a display device using the adhesive for bonding the front plate for a display device.

Hereinafter, the present invention will be described in more detail by way of examples, but the invention is not limited to the examples.

(Example 1)

Using a homogeneous dispersion type agitating mixer ("Homodisper L Type" manufactured by PRIMIX Co., Ltd.), phenoxy diethylene glycol acrylate as a monofunctional radically polymerizable compound was uniformly stirred and stirred at a stirring speed of 3000 rpm (Daicel-Cytec) "EBECRYL 110" manufactured by the company) 40 parts by weight, a homopolymer of phenoxy diethylene glycol acrylate (glass transition temperature -15 ° C, weight average molecular weight 30,000) 50 parts by weight, as a polyfunctional self 10 parts by weight of a tricyclodecane dimethanol diacrylate ("IRR-214K" manufactured by Daicel-Cytec Co., Ltd.) of a radical polymerizable compound, 1-hydroxycyclohexyl phenyl ketone as a photoradical polymerization initiator ( 1 part by weight of "IRGACURE 184" manufactured by BASF Japan Co., Ltd., 2 parts by weight of benzammonium peroxide ("Nyper BW" manufactured by NOF Corporation) as a thermal radical polymerization initiator, and γ as a decane coupling agent Further, 1 part by weight of glycidoxypropylmethyldiethoxydecane ("KBM-403" manufactured by Shin-Etsu Silicones Co., Ltd.) was obtained, and an adhesive for bonding the front plate for a display device was obtained.

(Example 2)

40 parts by weight of decylphenyltetraethylene glycol acrylate ("Light Acrylate NP-4EA" manufactured by Kyoeisha Chemical Co., Ltd.) was added as a monofunctional radically polymerizable compound instead of phenoxy diethylene glycol acrylate. And a homopolymer of nonylphenyltetraethylene glycol acrylate (glass transition temperature -25 ° C, weight average molecular weight 50,000) 50 parts by weight instead of phenoxy diethylene glycol acrylate homopolymer, in addition to this An adhesive for bonding the front plate for a display device was obtained in the same manner as in Example 1.

(Example 3)

As a monofunctional radically polymerizable compound, 40 parts by weight of 2-ethylhexyl diethylene glycol acrylate ("Light Acrylate EHDG-A" manufactured by Kyoeisha Chemical Co., Ltd.) was added instead of phenoxy diethylene glycol acrylate. And blending a homopolymer of 2-ethylhexyl diethylene glycol acrylate (glass transition temperature -30 ° C, weight average molecular weight 70,000) 50 parts by weight in place of the homopolymer of phenoxy diethylene glycol acrylate, Except for this, an adhesive for bonding the front plate for a display device was obtained in the same manner as in Example 1.

(Example 4)

The amount of the phenoxy diethylene glycol acrylate is changed to 90 parts by weight, and the amount of the phenoxy diethylene glycol acrylate homopolymer is changed to 5 parts by weight. In the same manner, an adhesive for bonding the front plate for a display device is obtained.

(Example 5)

The amount of the phenoxy diethylene glycol acrylate is changed to 5 parts by weight, and the amount of the phenoxy diethylene glycol acrylate homopolymer is changed to 90 parts by weight. In the same manner, an adhesive for bonding the front plate for a display device is obtained.

(Example 6)

The same procedure as in Example 1 except that the amount of the phenoxy diethylene glycol acrylate was changed to 49.5 parts by weight, and the amount of the tricyclodecane dimethanol diacrylate was changed to 0.5 part by weight. An adhesive for bonding the front plate for the display device is obtained.

(Example 7)

The same manner as in Example 1 except that the amount of the phenoxy diethylene glycol acrylate was changed to 10 parts by weight, and the amount of the tricyclodecane dimethanol diacrylate was changed to 40 parts by weight. An adhesive for bonding the front plate for the display device is obtained.

(Example 8)

An adhesive for bonding the front plate for a display device was obtained in the same manner as in Example 1 except that benzoyl peroxide was not formulated.

(Example 9)

As a monofunctional radically polymerizable compound, 40 parts by weight of 2-hydroxy-3-phenoxypropyl acrylate (trade name "EPOXY ESTER M-600A" manufactured by Kyoeisha Chemical Co., Ltd.) was added instead of phenoxydiethylene. Alcohol acrylate, and a homopolymer of 2-hydroxy-3-phenoxypropyl acrylate (glass transition temperature 15 ° C, weight average molecular weight 50,000) 50 parts by weight instead of phenoxy diethylene glycol acrylate An adhesive for bonding the front plate for a display device was obtained in the same manner as in Example 1 except for the above.

(Embodiment 10)

As a monofunctional radically polymerizable compound, dicyclopentenyloxyethyl acrylate (a "Fancryl FA" manufactured by Hitachi Chemical Co., Ltd.) is prepared as a monofunctional radically polymerizable compound having a substituent represented by the formula (2-2). -512AS") 40 parts by weight instead of phenoxy diethylene glycol acrylate, and 50 parts by weight of a homopolymer of a dicyclopentenyloxyethyl acrylate (glass transition temperature 10 ° C, weight average molecular weight 80,000) An adhesive for bonding the front plate for a display device was obtained in the same manner as in Example 1 except that a homopolymer of phenoxy diethylene glycol acrylate was used.

(Comparative Example 1)

A device for bonding a display device was obtained in the same manner as in Example 1 except that the phenoxy diethylene glycol acrylate was not blended and the amount of the tricyclodecane dimethanol diacrylate was changed to 50 parts by weight. Use the adhesive of the front plate.

(Comparative Example 2)

40 parts by weight of methoxy-triethylene glycol acrylate ("Light Acrylate MTG-A" manufactured by Kyoeisha Chemical Co., Ltd.) was added as a monofunctional radically polymerizable compound instead of phenoxy diethylene glycol acrylate. And adjust 50 parts by weight of a homopolymer of methoxy-triethylene glycol acrylate (glass transition temperature - 50 ° C, weight average molecular weight 40,000) instead of homopolymer of phenoxy diethylene glycol acrylate, An adhesive for bonding the front plate for a display device was obtained in the same manner as in Example 1.

(Comparative Example 3)

As a monofunctional radically polymerizable compound, 40 parts by weight of 2-ethylhexyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) was added in place of phenoxy diethylene glycol acrylate, and a homopolymer of 2-ethylhexyl acrylate was prepared. (Glass transfer temperature - 50 ° C) 50 parts by weight in place of the homopolymer of phenoxy diethylene glycol acrylate, except that the front plate for the display device was attached in the same manner as in Example 1. Agent.

(Comparative Example 4)

The same procedure as in Example 1 was carried out except that the homopolymer of phenoxy diethylene glycol acrylate was not blended, and the amount of the phenoxy diethylene glycol acrylate was changed to 90 parts by weight. Adhesive for the front plate of the display device is attached.

(Comparative Example 5)

40 parts by weight of methoxy-triethylene glycol acrylate ("Light Acrylate MTG-A" manufactured by Kyoeisha Chemical Co., Ltd.) was added as a monofunctional radically polymerizable compound instead of phenoxy diethylene glycol acrylate. Except for this, an adhesive for bonding the front plate for a display device was obtained in the same manner as in Example 1.

(Comparative Example 6)

Blending polyester resin ("Vylon 500" manufactured by Toyobo Co., Ltd.) 50 An adhesive for bonding the front plate for a display device was obtained in the same manner as in Example 1 except that a homopolymer of phenoxy diethylene glycol acrylate was used instead of the weight.

(Comparative Example 7)

A device for bonding a display device was obtained in the same manner as in Example 1 except that tricyclodecane dimethanol diacrylate was not added and the amount of the phenoxy diethylene glycol acrylate was changed to 50 parts by weight. Use the adhesive of the front plate.

<evaluation>

The following evaluations were carried out for the adhesives for bonding the front sheets for display devices obtained in Examples 1 to 10 and Comparative Examples 1 to 7. The results are shown in Tables 1 and 2.

(1) Viscosity

The adhesives of the adhesives for bonding the front sheets for display devices obtained in Examples 1 to 10 and Comparative Examples 1 to 7 were measured at 25 ° C and 2.5 rpm using an E-type viscometer.

(2) Compatibility

The adhesives for bonding the front plates for display devices obtained in Examples 1 to 10 and Comparative Examples 1 to 7 were visually observed, and the case of transparency was set to "○", and the case of opacity was set to "×". The compatibility of the monomer component and the polymer component was evaluated.

(3) Transparency of hardened material

The adhesives for bonding the front plates for display devices obtained in Examples 1 to 10 and Comparative Examples 1 to 7 were irradiated with ultraviolet rays of 3000 mJ/cm ² to form a film having a thickness of 300 μm, and light having a wavelength of 405 nm was used. The case where the penetration rate is 90% or more is set to "○", and the case where the penetration rate is less than 90% is "x", and the transparency is evaluated.

(4) Moisture resistance of hardened materials

The adhesives for bonding the front plates for display devices obtained in Examples 1 to 10 and Comparative Examples 1 to 7 were irradiated with ultraviolet rays of 3000 mJ/cm ² to form a film having a thickness of 300 μm, and the obtained film was allowed to stand. Place in a thermostat at 85 ° C, 85% RH for 500 hours. After the film was taken out from the constant temperature bath, it was visually confirmed, and when it was not observed that white turbidity was observed, it was set to "○", and when a little white turbidity was observed, it was set to "△", and the situation of white turbidity was clearly observed. When it is set to "x", the moisture resistance of the cured product is evaluated.

Further, when the adhesive for bonding the front plate for a display device obtained in Comparative Example 1 was used, the evaluation of moisture resistance could not be performed.

(5) Adhesiveness 1 (after photohardening)

The adhesives for bonding the front plates for display devices obtained in Examples 1 to 10 and Comparative Examples 1 to 7 were applied to PET (Indium Tin Oxides) by vapor deposition using a wire bar. Polyethylene terephthalate (polyethylene terephthalate) (manufactured by Teijin Co., Ltd.) was laminated with glass. Then, using a metal halide lamp, an ultraviolet ray of 3,000 mJ/cm ^{2 was} irradiated to harden the adhesive, and a polarizing plate for evaluation was produced.

The 180° peel strength of the obtained polarizing plate for evaluation was measured under the conditions of a peeling speed of 5 mm/min using a universal testing machine ("EZ Graph" manufactured by Shimadzu Corporation). When the peeling strength is 50 N/25 mm or more, it is set to "○", and when it is 20 N/25 mm or more and less than 50 N/25 mm, it is set to "△", which will be less than 20 N/25 mm. The situation is set to "X", The adhesion was evaluated.

(6) Adhesive 2 (after thermal hardening)

The adhesive for bonding the front plate for a display device obtained in Examples 1 to 10 and Comparative Examples 1 to 7 was applied to PET (manufactured by Teijin Co., Ltd.) on which ITO was vapor-deposited, using a wire bar. Fit the glass. The polarizing plate for evaluation was produced by hardening the ultraviolet rays without heating the adhesive at 80 ° C for 1 hour.

The 180° peel strength of the obtained polarizing plate for evaluation was measured under the conditions of a peeling speed of 5 mm/min using a universal testing machine ("EZ Graph" manufactured by Shimadzu Corporation). When the peeling strength is 50 N/25 mm or more, it is set to "○", and when it is 20 N/25 mm or more and less than 50 N/25 mm, it is set to "△", which will be less than 20 N/25 mm. In the case of "X", the adhesion is evaluated.

Further, regarding the adhesive for bonding the front plate for a display device obtained in Example 8, since the thermal radical polymerization initiator was not used, the evaluation of the adhesion property 2 was not performed.

(Manufacturing Example 1)

(Preparation of coenzyme A)

Using a homogeneous dispersion type agitating mixer ("Homodisper L Type" manufactured by PRIMIX Co., Ltd.), phenoxy diethylene glycol acrylate as a monofunctional radically polymerizable compound was uniformly stirred and stirred at a stirring speed of 3000 rpm (Daicel- "EBECRYL 110" manufactured by Cytec Corporation) 5 parts by weight, a homopolymer of phenoxy diethylene glycol acrylate (glass transition temperature -15 ° C, weight average molecular weight 30,000) 90 parts by weight, as polyfunctional radical polymerization 5 parts by weight of tricyclodecane dimethanol diacrylate ("IRR-214K" manufactured by Daicel-Cytec Co., Ltd.), 1-hydroxycyclohexyl phenyl ketone as a photoradical polymerization initiator (BASF Japan Co., Ltd.) 1 part by weight of "IRGACURE 184" manufactured by the company, 2 parts by weight of benzammonium peroxide ("Nyper BW" manufactured by NOF Corporation) as a thermal radical polymerization initiator, and γ-glycidyl acrylate as a decane coupling agent Periton A was obtained by using 1 part by weight of oxypropylmethyldiethoxydecane ("KBE-402" manufactured by Shin-Etsu Silicones Co., Ltd.).

(Manufacturing Example 2)

(Preparation of coenzyme B)

The amount of the phenoxy diethylene glycol acrylate is changed to 30 parts by weight, and the amount of the phenoxy diethylene glycol acrylate homopolymer is changed to 65 parts by weight. 1 The cofferdam B was obtained in the same manner.

(Manufacturing Example 3)

(Preparation of coenzyme C)

5 parts by weight of decyl diethylene glycol acrylate in place of phenoxy phenyltetraethylene glycol acrylate ("Light Acrylate NP-4EA" manufactured by Kyoeisha Chemical Co., Ltd.) In the same manner as in Production Example 1, except that 90 parts by weight of a homopolymer of acrylate (glass transition temperature - 25 ° C, weight average molecular weight: 50,000) was used instead of the homopolymer of phenoxy diethylene glycol acrylate. Obtaining a coenzyme C.

(Manufacturing Example 4)

(Preparation of coenzyme D)

5 parts by weight of 2-ethylhexyl diethylene glycol acrylate ("Light Acrylate EHDG-A" manufactured by Kyoeisha Chemical Co., Ltd.) was added to replace phenoxy diethylene glycol acrylate, and 2-ethylhexyldiethyl acrylate was prepared. A homopolymer of a diol acrylate (glass transition temperature: -30 ° C, weight average molecular weight: 70,000) was used in the same manner as in Production Example 1 except that 90 parts by weight of a homopolymer of phenoxy diethylene glycol acrylate was used instead of the homopolymer of phenoxy diethylene glycol acrylate. The cofferdam D is obtained in the same manner.

(Manufacturing Example 5)

(Preparation of coenzyme E)

The amount of the phenoxy diethylene glycol acrylate is changed to 1 part by weight, and the amount of the phenoxy diethylene glycol acrylate homopolymer is changed to 94 parts by weight. 1 The cofferdam E was obtained in the same manner.

(Manufacturing Example 6)

(Preparation of filler A)

Using a uniform dispersion type agitating mixer ("Homodisper L Type" manufactured by PRIMIX Co., Ltd.) at a stirring speed of 3000 rpm, uniformly 45 parts by weight of a phenoxy diethylene glycol acrylate ("EBECRYL 110" manufactured by Daicel-Cytec Co., Ltd.) as a monofunctional radically polymerizable compound, and a homopolymer of phenoxy diethylene glycol acrylate ( Glass transfer temperature: -15 ° C, weight average molecular weight: 30,000) 50 parts by weight, tricyclodecane dimethanol diacrylate ("IRR-214K" manufactured by Daicel-Cytec Co., Ltd.) as a polyfunctional radical polymerizable compound 1 part by weight of 1-hydroxycyclohexyl phenyl ketone ("IRGACURE 184" manufactured by BASF Japan Co., Ltd.) as a photoradical polymerization initiator, and benzammonium peroxide as a thermal radical polymerization initiator 2 parts by weight of "Nyper BW" manufactured by Oil Company, and γ-glycidoxypropylmethyldiethoxy decane as a decane coupling agent ("KBE-402" manufactured by Shin-Etsu Silicones Co., Ltd.) 1 The filler A was obtained in parts by weight.

(Manufacturing Example 7)

(Preparation of filler B)

The amount of the phenoxy diethylene glycol acrylate is changed to 90 parts by weight, and the amount of the phenoxy diethylene glycol acrylate homopolymer is changed to 5 parts by weight. 6 Filler B was obtained in the same manner.

(Manufacturing Example 8)

(Preparation of filler C)

45 parts by weight of decyl phenyltetraethylene glycol acrylate ("Light Acrylate NP-4EA" manufactured by Kyoeisha Chemical Co., Ltd.) was used instead of phenoxy diethylene glycol acrylate to prepare nonylphenyltetraethylene glycol. In the same manner as in Production Example 6, except that 50 parts by weight of a homopolymer of acrylate (glass transition temperature - 25 ° C, weight average molecular weight: 50,000) was used instead of the homopolymer of phenoxy diethylene glycol acrylate. Filler C was obtained.

(Manufacturing Example 9)

(Preparation of filler D)

45 parts by weight of 2-ethylhexyl diethylene glycol acrylate ("Light Acrylate EHDG-A" manufactured by Kyoeisha Chemical Co., Ltd.) was used instead of phenoxy diethylene glycol acrylate to prepare 2-ethylhexyldiethyl The same procedure as in Production Example 6 except that 50 parts by weight of a homopolymer of a diol acrylate (glass transition temperature: -30 ° C, weight average molecular weight: 70,000) was used instead of the homopolymer of phenoxy diethylene glycol acrylate. The filler D is obtained in the same manner.

(Manufacturing Example 10)

(Preparation of Filler E)

The amount of the phenoxy diethylene glycol acrylate is changed to 35 parts by weight, and the amount of the phenoxy diethylene glycol acrylate homopolymer is changed to 60 parts by weight. 6 Filler E was obtained in the same manner.

<evaluation>

The following evaluations were carried out for the cofferdams A to E and the fillers A to E obtained in Production Examples 1 to 10. The results are shown in Table 3.

(1) Viscosity

The viscosity of the cofferdams A to E and the fillers A to E was measured at 25 ° C and 2.5 rpm using an E-type viscometer.

(2) Compatibility

The cofferdams A to E and the fillers A to E were visually observed, and the case of transparency was set to "○", and the case of opacity was set to "x", and the compatibility of the monomer component and the polymer component was evaluated.

(3) Transparency of hardened material

The sputum A~E and the fillers A to E were irradiated with ultraviolet rays of 3000 mJ/cm ² to form a film having a thickness of 300 μm, and the transmittance of light having a wavelength of 405 nm was 90% or more, and it was set to "○". Transparency was evaluated by setting "X" to less than 90%.

(4) Moisture resistance of hardened materials

The sputum agents A to E and the fillers A to E were irradiated with ultraviolet rays of 3000 mJ/cm ² to prepare a film having a thickness of 300 μm, and the obtained film was statically placed in a thermostat bath at 85 ° C and 85% RH for 500 hours. After the film was taken out from the constant temperature bath, it was visually confirmed that the case where no white turbidity was observed and was transparent was set to "○", and the case where a little white turbidity was observed was set to "△", and the situation of white turbidity was clearly observed. The "x" was used to evaluate the moisture resistance of the cured product.

(5) Adhesiveness

The cofferdams A to E and the fillers A to E were applied to PET (manufactured by Teijin Co., Ltd.) on which ITO was vapor-deposited using a wire bar, and the glass was bonded thereto. Then, using a metal halide lamp, an ultraviolet ray of 3,000 mJ/cm ^{2 was} irradiated to harden the adhesive, and a polarizing plate for evaluation was produced.

The 180° peel strength of the obtained polarizing plate for evaluation was measured under the conditions of a peeling speed of 5 mm/min using a universal testing machine ("EZ Graph" manufactured by Shimadzu Corporation). When the peeling strength is 50 N/25 mm or more, it is set to "○", and when it is 20 N/25 mm or more and less than 50 N/25 mm, it is set to "△", which will be less than 20 N/25 mm. In the case of "X", the adhesion is evaluated.

(Example 11)

The cofferdam A was applied to a frame shape using a dispenser ("SHOTMASTER 3" manufactured by Musashi Engineering Co., Ltd.) in the peripheral portion of the liquid crystal panel. Then, the filler A was applied to the frame of the cofferdam A of the liquid crystal panel using a dispenser. A glass plate (alkali-free glass, thickness 0.7 mm) was attached to the liquid crystal panel coated with the cofferant A and the filler A as a front plate, and a metal halide lamp was used to irradiate ultraviolet rays of 3000 mJ/cm ² to form a cofferdam. A and the filler A were hardened to produce a display device.

The obtained display device was visually confirmed, and as a result, the cofferdam and the filler did not leak or flow out, and no boundary line between the cofferant and the filler was observed.

(Embodiment 12)

A display device was produced in the same manner as in Example 11 except that the filler B was used instead of the filler A.

The obtained display device was visually confirmed, and as a result, the cofferdam and the filler did not leak or flow out, and no boundary line between the cofferant and the filler was observed.

(Example 13)

A display device was produced in the same manner as in Example 11 except that the cofferdam agent B was used instead of the cofferdam A.

The obtained display device was visually confirmed, and as a result, the cofferdam and the filler did not leak or flow out, and no boundary line between the cofferant and the filler was observed.

(Example 14)

A display device was produced in the same manner as in Example 11 except that the filler B was used instead of the filler A and the cofferdam agent B was used instead of the cofferdam A.

Visually confirm the obtained display device, and the results of the cofferdam and filler No leakage or outflow was observed, and no boundary line between the cofferant and the filler was observed.

(Example 15)

A display device was produced in the same manner as in Example 11 except that the filler C was used instead of the filler A and the cofferdam agent C was used instead of the cofferdam A.

The obtained display device was visually confirmed, and as a result, the cofferdam and the filler did not leak or flow out, and no boundary line between the cofferant and the filler was observed.

(Embodiment 16)

A display device was produced in the same manner as in Example 11 except that the filler D was used instead of the filler A and the cofferdam agent D was used instead of the cofferdam A.

The obtained display device was visually confirmed, and as a result, the cofferdam and the filler did not leak or flow out, and no boundary line between the cofferant and the filler was observed.

(Example 17)

The cofferdam A was applied to a frame shape using a dispenser ("SHOTMASTER 3" manufactured by Musashi Engineering Co., Ltd.) in the peripheral portion of the liquid crystal panel. Then, the filler A was applied to the frame of the cofferdam A of the liquid crystal panel using a dispenser. A glass plate (alkali-free glass, thickness 0.7 mm) provided with a light-shielding portion that does not transmit light to the periphery is attached to the liquid crystal panel coated with the cofferdam A and the filler A as a front plate, and a metal halide lamp is used for irradiation. Ultraviolet rays of 3000 mJ/cm ² harden the cofferdam A and the filler A. Then, by heating at 60 ° C for 1 hour, the portion of the coagulant A and the filler A which were shielded by the light shielding portion were cured to prepare a display device.

The obtained display device was visually confirmed, and as a result, the cofferdam and the filler did not leak or flow out, and no boundary line between the cofferant and the filler was observed.

(Reference example 1)

A display device was produced in the same manner as in Example 11 except that the filler A was applied to the entire portion of the front panel of the liquid crystal panel by using the dispenser A.

The obtained display device was visually confirmed, and it was confirmed that the filler A leaked from between the liquid crystal panel and the front plate.

(Reference example 2)

A display device was produced in the same manner as in Example 11 except that the cofferdam agent B was used instead of the cofferant A, and the filler E was used instead of the filler A.

The obtained display device was visually confirmed, and as a result, it was confirmed that the cofferdam was broken and the filler leaked out.

(Reference Example 3)

A display device was produced in the same manner as in Example 11 except that the cofferdam A was used instead of the coagulant A, and the filler B was used instead of the filler A.

The obtained display device was visually confirmed, and as a result, the cofferdam and the filler did not leak or flow out, but the strain of the glass was confirmed at the boundary line between the cofferant and the filler.

(Reference example 4)

A display device was produced in the same manner as in Example 11 except that the cofferdam agent C was used instead of the cofferdam A.

The obtained display device was visually confirmed, and as a result, the cofferdam and the filler did not leak or flow out, but the boundary between the cofferant and the filler was confirmed.

[Industrial availability]

According to the present invention, it is possible to provide a transparency and an excellent moisture resistance of a cured product, and the polarity of the substrate of the front plate and the front plate to be bonded is greatly different. In this case, it is also possible to sufficiently adhere the adhesive for bonding the front plate and the substrate to the front plate for the display device. Moreover, according to the present invention, it is possible to provide a display device using the adhesive for bonding the front plate for a display device.

1‧‧‧ front board

2‧‧‧Substrate

3‧‧‧Adhesive for bonding the front panel of the display device

4‧‧‧Lighting Department

5‧‧‧Transmission Department

Fig. 1 is a cross-sectional view showing an example of a display device using the adhesive for bonding a front plate for a display device of the present invention.

Claims (8)

An adhesive for bonding a front plate for a display device, which is an adhesive for bonding a substrate of a display device and a front plate, which comprises a monofunctional radical polymerization having a hydrophilic group and a hydrophobic group in the molecule a compound, a homopolymer of the monofunctional radically polymerizable compound, a polyfunctional radically polymerizable compound, and a photoradical polymerization initiator, wherein the monofunctional radical having a hydrophilic group and a hydrophobic group in the above molecule The polymerizable compound is 2-ethylhexyl diethylene glycol acrylate or a compound represented by the following formula (1). In the formula (1), R ¹ represents hydrogen or a methyl group, R ² represents a linear or branched saturated aliphatic hydrocarbon group having 1 to 6 carbon atoms, or a 2-hydroxypropyl group, and R ³ represents the following formula: a substituent represented by (2-1), (2-2), (2-3), or (2-4), and n represents an integer of 1 to 6, In the formula (2-1), R ⁴ represents hydrogen or a linear or branched alkyl group having 1 to 12 carbon atoms. An adhesive for bonding a front plate for a display device according to the first aspect of the patent application, which contains a thermal radical polymerization initiator. An adhesive group for bonding a front plate for a display device, which is used for bonding a substrate of a display device to a front plate, which is composed of a substrate and a front plate at a peripheral portion of the display device a dam agent, and a filler on the inner side of the cofferdam and a base material, and the filler is used in claim 1 or 2 of the patent application scope. The adhesive for the front plate for a display device is bonded, and each of the same monofunctional radically polymerizable compound is contained, and the monofunctional radical polymerizable a homopolymer, a polyfunctional radically polymerizable compound, and a photoradical polymerization initiator, wherein the content of the homopolymer of the monofunctional radically polymerizable compound is higher than that of the above-mentioned filler The viscosity of the above-mentioned cofferdam was measured using an E-type viscometer at 25 ° C and 2.5 rpm. The viscosity of the above-mentioned filler was measured using an E-type viscometer at 25 ° C and 2.5 rpm. Ten thousand times. A manufacturing method of a display device for bonding a substrate and a front plate with an adhesive for bonding a front plate for a display device, comprising the steps of: applying the first or second aspect of the patent application; a step of applying an adhesive of a front plate for a display device to at least one of the substrate and the front plate; and bonding the substrate and the front plate to expose the display by irradiation of light The step of hardening the device with an adhesive of the front plate. The method of manufacturing a display device according to the fourth aspect of the invention, wherein the substrate and the front plate are bonded to each other by using an adhesive for bonding the front plate of the display device by irradiation with light, by irradiating light And heating is performed to harden the above-mentioned adhesive for bonding the front plate for a display device. A method of manufacturing a display device for bonding a substrate and a front plate using an adhesive for bonding a front plate for a display device, comprising the steps of: surrounding a peripheral portion of at least one of the substrate and the front plate; a step of applying a cofferant to a frame, applying a filler to the frame of the coated cofferant, and a step of bonding the base material and the front plate to the base sheet and the filler by the coating agent, and the step of curing the damper and the filler by irradiation with light, and applying the patent range of the damper and the filler The cofferdam and filler for the adhesive group of the third item for bonding the display device. The method of manufacturing a display device according to claim 6, wherein the step of bonding the substrate and the front plate via a damper and a filler, and irradiating light to harden the damper and the filler The damper and the filler are cured by irradiation with light and heating. A display device using an adhesive for bonding a front plate for a display device according to item 1 or 2 of the patent application, or a bonding device for attaching a front plate for a display device according to item 3 of the patent application Group of agents.